结直肠癌组织中MMR蛋白表达、MSI、RAS和BRAF基因突变与临床病理特征的关系OACSTPCD

Objective To investigate the relationship between the mismatch repair protein(MMR protein)expression,microsatellite instability(MSI),rat sarcoma gene(RAS)and carcinogenic homolog B1 gene(BRAF)gene mutation in colorectal cancer(CRC)tissues with the clinicopathologic features.Methods The tumor tissue and blood samples in 352 patients with colorectal cancer receiving the radical operation treatment and the mass tumor tissue and blood samples in 42 patients with non-intestinal cancer in this hospital from January to December 2022 were collected.The immunohistochemistry was used to detect the MMR protein,the first generation sequencing fragment analysis was performed to detect MSI,and the real-time quantitative PCR was used to detect the gene mutation status of KRAS,NRAS and BRAF.The relationship between MMR protein expression,MSI and three gene mutation states with the clinicopathologic features of CRC was ana-lyzed.Results In the tumor tissues of 352 patients with CRC,the 29 cases(8.2％)of MMR(dMMR)and 26 cases(7.4％)of MSI-H were detected respectively.The mutation rates of KRAS,NRAS,BRAF genes were 45.7％(161 cases),3.7％(13 cases)and 3.1％(11 cases),respectively.The factors associated with dMMR were the age,mucinous carcinoma and originated from right-sided colon cancer.The factors associated with MSI-H included the low age,family tumor history and originated from right-sided colon cancer(P＜0.05).High mutation rates of KRAS and NRAS genes were related with mucinous adenocarcinoma and lymph node metastasis,respectively.High BRAF mutation rate was associated with poor differentiation and originated from fright-sided colon cancer(P＜0.05).The BRAF gene mutation was related with dMMR and MSI-H.Conclusion The MMR protein expression,MSI status,and the gene mutations of KRAS,NRAS and BRAF are correlated with different clinicopathologic features.The combined detection of these five molecular mark-ers could be used to classify the tumor molecules,which further provides the theoretical basis for the individu-alized precision diagnosis and treatment of the patients with CRC.